Jun 21, 2013

    4-min workout may just do the trick

    ANYONE who exercises always thinks of how long, how far, and how intensely they have to work in order to achieve their fitness goals.

    What they're really asking is, "How little exercise can I get away with?"

    The answer, it seems, may be four minutes.

    In a study which was published last month in the journal PLoS One, researchers from the Norwegian University of Science and Technology in Trondheim, Norway, and other institutions attempted to delineate the minimum amount of exercise required to develop appreciable endurance and health gains.

    Dr Arnt Erik Tjonna, a postdoctoral fellow at the Norwegian University of Science and Technology, who led the study, had found that it was possible to get results from 16 minutes of high-intensity intervals. This time, he wanted to determine whether a single, strenuous four-minute workout would effectively improve health and fitness.

    Researchers gathered 26 overweight-but-otherwise-healthy middle-aged men. Half began a supervised exercise programme that had them warming up, then running on a treadmill at 90 per cent of their maximal heart rate for four four-minute intervals, with three minutes of slow walking between, followed by a brief cooldown. The entire session was repeated three times a week for 10 weeks.

    The second group completed only one four-minute strenuous run. They, too, exercised three times a week for 10 weeks.

    At the end of the programme, metabolic and cardiovascular health had improved in both groups, despite the fact that few of the men had lost much body fat. Almost all displayed better blood-sugar control and blood- pressure profiles.

    "This is not a weight-loss programme," says Dr Tjonna. It is, instead, "a suggestion for how people can make a kick-start for better fitness", or maintain fitness already gained.

    The workout can be practised anywhere. Sprint uphill for four minutes or race up multiple flights of steps. Cycle, swim or even walk briskly, as long as you raise your heart rate sufficiently for four minutes. Obviously, consult your doctor first if you haven't been active in the past.

    Says Dr Tjonna: "Everyone, we think, has time for this kind of exercise three times a week."